In a pending patent application, Ser. No. 11/249,223, the parent of which is Ser. No. 10/756,015 filed Jan. 13, 2004, a secondary battery was disclosed which comprised a positive electrode of lead, a negative electrode of zinc and an alkaline electrolyte. This battery shows considerable promise, including low cost and high energy density. It is handicapped, however, by weight, due to the lead electrode, which restricts applications where mobility is needed. Secondly, the toxicity of lead is a drawback.